SilverStone SX650-G PSU Review: Lots Of Power In A Small Form Factor

Load Regulation, Hold-Up Time & Inrush Current

To learn more about our PSU tests and methodology, please check out How We Test Power Supply Units. 

Primary Rails And 5VSB Load Regulation

Load Regulation testing is detailed here.

Hold-Up Time

Our hold-up time tests are described in detail here.

The hold-up time we observed exceeded 17ms, while the power-good signal lasted longer than 16ms.

Inrush Current

For details on our inrush current testing, please click here.

Measured inrush currents were at normal levels under both voltage inputs.

Load Regulation And Efficiency Measurements

The first set of tests reveals the stability of the voltage rails and the SX650-G’s efficiency. The applied load equals (approximately) 10 to 110 percent of the PSU's maximum load in increments of 10 percentage points.

We conducted two additional tests. During the first, we stressed the two minor rails (5V and 3.3V) with a high load, while the load at +12V was only 0.1A. This test reveals whether a PSU is compatible with Intel's C6/C7 sleep states or not. In the second test, we determined the maximum load the +12V rail could handle with minimal load on the minor rails.

Test #12V5V3.3V5VSBDC/AC (Watts)EfficiencyFan Speed
PSU Noise
Temps (In/Out)PF/AC Volts
13.576A1.976A1.973A0.981A64.83882.269%1117 RPM
19.4 dB(A)
28.189A2.955A2.965A1.181A129.76087.294%1117 RPM19.4 dB(A)38.52°C0.993
313.156A3.464A3.483A1.381A194.90289.754%1117 RPM19.4 dB(A)38.70°C0.994
418.128A3.964A3.970A1.583A259.79590.430%1117 RPM19.4 dB(A)39.16°C0.996
522.775A4.961A4.976A1.786A324.76390.430%1117 RPM19.4 dB(A)39.75°C0.997
627.436A5.951A5.987A1.991A389.72490.114%1117 RPM19.4 dB(A)40.35°C0.998
732.109A6.964A7.003A2.196A454.68589.461%1997 RPM34.1 dB(A)41.89°C0.998
836.796A7.966A8.020A2.401A519.66788.794%2265 RPM36.8 dB(A)43.22°C0.998
941.934A8.476A8.558A2.404A584.72887.917%2491 RPM41.0 dB(A)44.42°C0.998
1047.041A8.987A9.063A2.508A649.62687.191%2790 RPM44.7 dB(A)45.93°C0.998
1152.553A8.994A9.075A2.510A714.58086.381%2755 RPM44.6 dB(A)46.55°C0.998
CL10.099A13.019A13.006A0.005A109.91481.634%1117 RPM19.4 dB(A)43.82°C0.992
CL254.123A1.003A1.003A1.002A660.50787.522%2790 RPM44.7 dB(A)45.63°C0.998

The +12V rail demonstrated close to 1.3% deviation, while the 5V rail showed off even tighter load regulation at 1.18%. The 3.3V rail performed well enough at around 2.1%, and the 5VSB rail was at 2.64%.

SilverStone's SX650-G easily satisfied the 80 PLUS Gold specification's requirements, even under the tough conditions we applied.

Up through the 60% load test, SilverStone's SX650-G was nearly silent, despite an ambient temperature in the 38-40°C range. The fan kicked in hard during the 70% load test, though, and under full load it hit its peak speed (and close to 45 dB[A] noise).

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